I know its probably a silly question but I'll ask it all the same.

Why dont people run 4 barrel carbs on VW's ? The two reasons I can think of are

a) Wont fit under the decklid

b) Two twin barrels mean shorter inlet tract, less condensing issues etc.

But theoretically, there is no reason you couldnt set it up if you could make it fit right ?

I'm only thinking that a 450 Holley (smallest ? 4bbl around) is only about $300 rebuilt 2nd hand, sompared to about $800 for twin 40IDF's or Dellorto's. They should flow similar amounts of air, and jetting is abundant, as it knowledge / books on how to setup and tune.

Is it really a silly question ?

no you can get a four barrel manifold for a vw but i think the main reason that they are considered over kill in the fuel delivery( if im wrong somebody correct me)

isn't a bug spray a 4bbl holley carb for a beetle?

i thought it was a two barrel progressive like the webber
wheres lee when you need him his son has one on his bug

[Edited on 21-12-2004 by barls]
just found these pics



[Edited on 21-12-2004 by barls]

Bugsprays are a 2bbl non progressive - my old mans got one somewhere. They are a biatch to get parts for.

The one we had, was put back together by whoever we got it from, without reinstalling the main jet. We were wondering why we could never get it to run properly, and everytime it caught and started, it was with a huge cloud of black smoke.

We worked it out later

I thought about the fuel, but surely you could get smaller jets (say from the smaller 2 bbl holleys), and thus mix the high airflow of the 4bbl with the correct amount of fuel flow ?

Personally I've only ever seen them on draw through turbo / supercharged setups on drag vw's. I'm curious to see if it could be done on a street vw though.

its possible i stayed away from the non progressive carbs when i did mine i still stand by the progressive webber copy off a lada niva is the best carb ive ever used

I agree 100% - my old mans 62 runs a 32/36DGAV progressive on a 1641 with standard heads and cam and it is one of the most driveable beetles around.

the vaccum secondary is much better than the mechanical and if its the one with the electronic choke as well. a dream to run

there are a few US kits for these.

I believe condensing IS the big problem with these.
I think it is to do with the fact that on a single there is vacuum there ALL the time.
With the 4 barrel it is not

A bit like the reverse of why a 4 into 1 exhaust is better with scavenging the exhaust gas out.
I think this is why a prog is a easier set up than a single IDF??

Dunno - but they aint popular in the states. If you are a SBO maybe ask Ryan. Pretty sure he has answered this b4.

Your answer makes sense.

I was sure there would be a logical reason....

A 4 barrel holley is plenium type carb, meaning that all 4 barrels can feed any cylinder with an open inlet valve. What this means is that setting the carb up is quite difficult compared to twin IDFs or the like. Also the other big problem is manifold, a straight shot into the inlet port is best and as you can imagine this would be impossible with a centre mounted 4 barrel carb.
In saying that someone on the Cal Look forum claims to have had good results with this setup.
Also the smallest 4 barrel Holley is a 390. I don't think these are made anymore.